This project encompasses a wide scope of statistical collaboration and consultation with laboratories and branches within the Division of Intramural Research (DIR), and with other neuroscience units outside NIH. Particular consideration is given to statistical planning and design of experiments, statistical analysis of data, and statistical inference. Examples of current studies include: clinical trial of bioequivalence of alpha- mannose-terminated glucocerebrosidase from natural and recombinant source, clinical course and long-term outcome of patients treated with Ceredase/TM in Gaucher's disease, evaluation of skeletal responses of patients with Gaucher's disease treated with Ceredase/TM ,longitudinal study of the clinical course of Fabry's disease (DMNB); clinical trials of felbamate for the treatment of intractable complex partial seizures, measurement of the effect of time from last seizure and seizure type on metabolic change as measured by PET, study of epilepsy progression to general tonic-clonic seizures (ERB); clinical trial of the effect of cyclosporine on lesion development in relapsing-remitting MS, modeling lesion recurrence in relapsing-remitting MS, clinical trial of DSG on lesion development in relapsing-remitting MS, monitoring MRI T2 weighted imaging in relapsing-remitting MS; determination of the role of B7:CD 28-CTLA-4 interaction in chronic relapsing EAE; examining the effect of accumulation of disease white matter in patients with relapsing-remitting MS (NIB); prevalence study of neurologic diseases in the Navajo tribe (ERB); study of abnormal facilitation response to transcranial magnetic stimulation in PD patients, identification of deficits associated with "over use" syndrome in pianists, three clinical trials of IV-IG in neuromuscular disorders, follow-up study of twins discordant for paralytic polio and subsequent post-polio syndrome; clinical trial of amantadine for the treatment of post-polio fatigue (MNB); evaluation of neuronal sprouting and behavioral recovery in hemiparkinsonian rats after amnion cell transplantation (SNB); validation study of consultations provided by U.S. drug information centers; incidence study of nervous system tumors in Israel; incidence study of motor neuron disease on Guam (NEB); development of Markov models for rapidly cycling bipolar disorder, examination of the relationship between bright light exposure and hot flashes in menopausal women (NIMH); studies of silent stroke risk factors and their implication for survival of a subsequent stroke, and risk of seizures following stroke.